Usually, the semiconductor sealing resin composition is required to be excellent in heat resistance, moisture resistance, electrical properties, adhesiveness and the like, and therefore it is generally an epoxy resin composition comprising an epoxy resin, a phenol-based curing agent, a curing accelerator and an inorganic filler. In addition, the semiconductor device has come to have a higher density, a less thickness and an increased number of pins with the advance of fine processing technology.
When such a semiconductor device, particularly a thin semiconductor device is produced, poor mold-releasing property of a sealing resin (for example, a cured product of an epoxy resin composition) from a mold in releasing a semiconductor device after seal-molding leads to generation of stress, resulting in problems such as cracking in the semiconductor element itself inside the semiconductor device or/and deterioration of adhesion properties in the interface between the cured product and the semiconductor element. In addition, in surface mounting of a semiconductor device, the semiconductor device is exposed to a high temperature of 200° C. or more during the solder reflow process with the use of a lead-free solder, resulting in detachment of the sealing resin composition from IC tips and the lead frame and in cracking of the package, and thus defects extremely reducing reliability have been generated.
Lately in addition, there have been more opportunities where a copper lead frame is used due to need of heat radiation property and copper oxidation causes deterioration of adhesion properties between a lead frame and a sealing resin composition, whereby much better adhesion properties have been required.
As a resin composition to meet such requirements, a sealing resin composition using a novel epoxy (Patent Literature 1), a sealing resin composition containing an amide compound (Patent Literature 2), a sealing resin composition containing a trace amount of triazole compound (Patent Literature 3), and the like are known. In the case that these are used, adhesiveness between a cured product of said sealing resin compositions and a lead frame and/or semiconductor element shortly after molding is excellent, but durabilities such as heat resistance, moisture resistance, electrical properties and the like are not enough because adhesive strength is reduced over time due to reduction of water absorption resistance and heat resistance of said cured product and further due to over time reduction of adhesive strength with oxidation of lead frame. In addition, a primer resin composition for semiconductor devices which contains an alkoxysilyl group-containing polyamide-imide resin such as Patent Literature 4 has been proposed.    Patent Literature 1: JP 2003-246836 A    Patent Literature 2: JP H10-324794 A    Patent Literature 3: JP 2006-335829 A    Patent Literature 4: JP 2006-241414 A